Right now the compass seems to be pointing in the direction of health care. That probably won’t change anytime soon:

In 1980, 1.4 million jobs in health care paid a middle class wage: $40,000 to $80,000 a year in today’s money. Now, the figure is 4.5 million.

The pay of registered nurses — now the third-largest middle-income occupation and one that continues to be overwhelmingly female — has risen strongly along with the increasing demands of the job. The median salary of $61,000 a year in 2012 was 55 percent greater, adjusted for inflation, than three decades earlier.

And it was about $9,000 more than the shriveled wages of, say, a phone company repairman, who would have been more likely to head a middle-class family in the 1980s. Back then, more than a quarter of middle-income jobs were in manufacturing, a sector long dominated by men. Today, it is just 13 percent.